Glass



CLARENCE B. PEREGRINE, OF CHARLEROI, BEN-NSYLVANIA,

ASSIGNOR 'IO MACBETH- EVANS GLASS COMPANY, A CORPORATION OF PENNSYLVANIA.

GLASS No Drawing:

To all whom it may concern.-

Be it known that I, CLARENCE R. Pean- GRINE, a citizen of the United States, residing at Gharleroi, in the county of Washington, and State of Pennsylvania, have invented a certain new and useful Glass, of which the following is a specification.

The invention relates to an improvement in glass and has for its objects, the proyr sion of an improvedrelatively dense Wh1te glass which may be used with thin shades and powerful illuminating elements and satisfactorily transmit and diffuse the light therefrom; the provision of a glass which may be cheaply made, which is workable, and which does not show the dead white color characteristic of the well known milk 'la'ss.

b Various foundation batches may be employed to which the coloring ingredients are added. One of such foundation' batches which I have found to be satisfactory is as follows:

Sand 977.5 parts Soda ash 67.5

Boraxsu 66 Litharge Zinc oxid 225 Niter v4O Limestone; 115 Salt 10' The foregoing batch, which approximates 1500 parts, if used without the coloring inhereinafter referred to, will produce a substantially I colorless clear glass, and various substitutes might be employed.

To the foregoing clear glass batch are added the coloring ingredients comprising the following compounds and quantities:

Hydrate of aluminum 260 parts. Sodium silico -fl1'1orid 151 The foundation batch together with the coloring compounds in powdered form are thoroughly mixed together and melted in the usual way.

The hydrate of aluminum (AI H O contains 34.6% of aluminum, so that the 260 parts of aluminum hydrate has an aluminum content of about 90 parts. Other aluminum compounds, such as China clay, and

Specification of Letters Patent.

. that lime-stone may feldspar, might be used instead of the hydrate, 1f an adjustment were-made so as to secure the proper amount of aluminum.

The sodium silico fluorid (Na SiF con tains 60.6% of fluorin, so that in the 151 parts of this compound there are about 91 parts of fluorin.

Other fiuorids might be used, such. as cryolite, sodium fluorid and fluorspar, or combinations of fluorids may be employed, the primary requirement being the securing of the proper amount of fluorin, which is the coloring agent. -However, if fluorspar is used alone it gives a relatively high calcium content resulting in a sandy, brittle glass, which is difiicult to work.

Patented J an. 6, 1920.

Application filed September 24, 1917. Serial No. 192,886.

It will also be understood that, aside from the substitution of equivalent conipounds, as above indicated, the proportions of aluminum and fluorin may be modified to a considerable extent and still produce a glass having the general characteristics of produced from the batch above set forth; For instance, the amount of fiuorin may be increasedas much as 50% or more, rendering the glass denser, the number of parts usable ranging from 90 to'140. Simi-' larly, the amount of aluminum used may range from 90 to 150 parts depending upon the density of the glass required and the thickness of the glass.

I have found that the zinc oxid is very highly desirable in the basic batch, improving the quality of the glass and rendering it more readily workable. Such compound also assists in relieving the glass of the dead white color of the old milk glasses. Similarly the lime-stone or some other ingredient containing calcium is very desirglass rendering it more viscous and thus preventing the fluorin gas from escaping too readily through the glass. Other ingredis ents tending to make the glass more viscous, such as lead oxid or barium carbonate, might be employed instead of the limestone. If fluorspar is usedas a partial substitute, for the be omitted, as in that case the calcium is supplied by thefluorspar. I

i have found that the use of the fluorspar toget-her with the sodium silico fluorid constisodium silico fluorid, the

tutes a most satisfactory way of introducaluminum and a compound containing ing the necessary fluorin, and it is also posfrom 90 to 140 parts of fluorin. sible to use other combinations-of fluorids 2. vA glass formed by fusing together a or combinations of compounds for supplymixture comprising approximately 1500 15 5 ing aluminum. parts of a foundation batch capable of pro- What I claim is: ducing substantially clear glass and includ- 1. A glass formed by fusing together a ing zinc oxid, with a compound containing mixture comprising iapproximately 1500 from 90 to 150 parts of aluminum-and a parts of a foundation batch capable of procompound containing from 90 to 140 parts 20 10 ducing substantially .clear glass, with a comof fluorin. pound containing from 90 to 150 parts of CLARENCE R. PERE GRINE. 

